Arsenic concentrations exceeding the U.S. Environmental Protection Agency (USEPA) current Maximum Contaminant Level (MCL) of 50 micrograms per liter are widespread in ground water in the Willamette Basin. The Oregon Water Resources Department and the U.S. Geological Survey began a cooperative study in the Willamette Basin in 1996. One goal...
This report presents results of an investigation of water and streambed-sediment quality in selected tributaries of the South Umpqua River. Concentrations of inorganic constituents in water (major and minor ions, nutrients, and trace elements) and streambed sediment (primarily trace elements), along with standard field parameters, are tabulated for samples collected...
The purposes of this report are to describe the quality of shallow ground water in alluvial aquifers of the Willamette Basin and to identify relationships between shallow ground-water quality and various natural and anthropogenic factors. Several natural and anthropogenic factors (soil characteristics, cumulative thickness of clay above open interval of...